A supporter of the ruling Islamic party Ennahda protests against another march during ceremonies marking the second anniversary of the Revolution, in Tunis, in January. Long before Tunisia ousted its dictator and inspired the North African pro-democracy movement, the small, relatively prosperous country had the more dubious distinction of exporting Islamic militants. Now experts say the flow of fighters is getting worse.

One night last December, national guardsmen burst into the hospital emergency room in this mountain town leading a young man, handcuffed and shot through the right buttock.

“I am a mujahid on the path of God,” he proclaimed, but disclosed no more, according to a hospital worker who asked not to be named because he wasn’t allowed to speak to media.

The young man, Saifeddine Chagroun, was shot and arrested while trying to sneak into Algeria en route to Syrian battlefields, says his lawyer. He is one of many would-be fighters signaling Islamist militancy that is increasingly spanning borders.

The Arab Spring has brought new freedoms, but also instability. Libya is swamped with weapons, which fueled an Islamist takeover of northern Mali last year. In Tunisia, revolution has weakened security and allowed a hardline conservative Salafi current to emerge.

For North Africa’s militants, that makes Tunisia a good place to traffic arms and recruit fighters. Authorities want to crack down harder, but lack resources. Lawyers warn that what they describe as scapegoating and alleged abuse of Salafi suspects could inflame an already tense situation.

US and Tunisian authorities are increasingly worried. This week Gen. Carter Ham, who heads the US Army’s Africa Command, said Al Qaeda was trying to get a foothold in Tunisia, while Tunisia’s interior ministry said it was creating “crisis cells” to watch for terrorist activity.

On March 17, North Africa’s premier militant group, Al Qaeda in the Islamic Maghreb, called on supporters to work against local secularists or fight government forces in Algeria and a French-led intervention in Mali.

Meanwhile, the families of young men like Mr. Chagroun are still groping for an explanation.

The path to radicalism

Chagroun grew up in the city of El Kef, in hilly country near the Algerian border. His family remember a lively, personable boy.

“He was especially close to his father – sometimes I’d get jealous!” says his aunt, Samira Ben Rejeb.

The family members were nibbling cake at home after the recent funeral of a relative. Chagroun’s mother, Latifa Ben Rejeb, got out a photograph of him and Samira kissed it.

“And in Tunis, anything new?” Samira said. Chagroun is under investigation by a Tunis court.

“No.”

Until his arrest, Chagroun studied sports education at university. He prayed with Salafi friends at a nearby mosque but was moderate himself, says his family. However, local Slim Ghrissi, who prays at the mosque, says Chagroun shared the Salafi goal of strictly Islamic governance.

Salafis have pushed that agenda since revolt ended persecution of conservative Muslims by former president Zine El ABidine Ben Ali. A few have also gotten violent, often over art they call blasphemous.

Last May a middle-school drama teacher named Rejeb Magri was walking through El Kef when he felt a fist smash into his head, he says. Instantly, men he describes as Salafis were showering him with blows and kicks. Then a hand yanked him up by the hair.

“It was Saifeddine Chagroun,” he says. “He looked into my eyes and said, ‘We’ll kill you one by one’.”

Mr. Magri was hospitalized with a broken jaw and clavicle, and four fewer teeth. His wife filed a complaint with police accusing Chagroun. Chagroun’s family insist he’s innocent, and have procured a statement from his university that says he was taking an exam on the day of the assault.

Authorities didn’t act on the complaint, but guilty or not, Chagroun became convinced that police were after him. His family think fear of arrest prompted his departure. Mr. Ghrissi says Chagroun also developed a mantra: “I’m a mujahid on the path of God.”

'One Muslim country'

Leading Tunisian Salafis have declared the country off-limits for armed struggle. Many Salafis say they reject violence on principle. For others, foreign conflicts offer a chance to fulfill what they call a religious duty to aid fellow Muslims.

"We see one Muslim country,” says Ghrissi. “And we support our brothers in Syria against Bashar al Assad.”

It’s unknown how many Tunisians have joined the revolt against Mr. Assad’s regime, which is increasingly dominated by Islamist militias. But earlier this week, a Tunis court said it would investigate networks suspected of funneling would-be fighters abroad.

For Tunisia, the fear is those fighters will return “more experienced and more fanatical,” says a Western official who spoke on condition of anonymity. The country’s porous border also makes it a channel for moving arms from Libya.

A December shootout between security forces and militants near the Algerian border uncovered a cache of explosives and ammunition, authorities said. Even larger caches of Ak-47’s, RPG’s, and munitions have since been found.

So far, trafficked weapons are destined for other countries, says the official. But they suggest cooperation among North African militants. So do the trajectories of men like Laroussi Derbali, a Tunisian laborer who ended up fighting in Algeria, apparently by way of neighboring Libya.

Mr. Derbali went to Libya for work in 2010 and broke contact with his family last August, says his brother, Said. In January, Laroussi was among 11 Tunisians accused of taking part in an attack on a gas plant near Algeria’s Libyan border that killed 29 attackers and 38 hostages.

Derbali is now jailed in Algeria. His brother speculates that he met people in Libya “who got inside his head.”

Chain reaction

Meanwhile, Tunisian police forces that bolstered Mr. Ben Ali’s regime are still recovering from its collapse, while the army is overstretched – problems compounded by “a kind of distrust between the police and the army,” says the official.

Still, security has tightenedsince a mob that included Salafis sacked the US embassy last September over a film lampooning the prophet Muhammed. Police got clear permission to use force against attacks and began arresting people for allegedly inciting violence, says a February report by the International Crisis Group.

Some lawyers, however, say authorities risk aggravating Salafis by targeting them disproportionately and veering into abuses such as beating suspects and bending procedures.

“It’s extremism against extremism,” says lawyer Jilani Lammouchi, who is defending suspects in the US embassy attack. “And for every action, there’s a reaction.”

Tunisia’s interior ministry and national guard didn’t reply to requests for comment on any aspect of this article.

Chagroun isn’t saying exactly why he headed for Syria. He hoped to avoid police at Tunis’ airport by going through Algeria. But national guardsmen stopped his car on a forest road near Ain Drahem, on the Algerian border.

Chagroun says he surrendered but was shot anyway by a panicky guardsman, according to his lawyer, Mehdi Zagrouba. National Guardsmen in Ain Drahem said they weren’t allowed to comment. The state newswire described guardsmen opening fire on a fleeing suspect who was carrying bullets, which Chagroun denies.

Today Chagroun is in El Kef’s prison, down the hill from his house. His mother visits him each Wednesday. He talks more to her now than to his father, she says.

“I think he wants to spare me the strain,” is how Mohamed Chagroun explains it. For now, he and his family are waiting and hoping “that his rights will be respected, and that families will look after their children and not let them stray.”